repositoryCache
com.google.common.cache.Cache<K,V> repositoryCache
This cache is for repositories and is explicitly _not_ static because we
want to store repo information per-user (and this class should be per-user).
We potentially could hold a separe static cache for public repo info
that applies to all users, but it wouldn't be able to contain user-specific
details like exact permissions (read/write/admin).
This representation of the repo holds details on whether the repo is
public/private, as well as whether the current user has pull/push/admin
access.